Wireless communication networks may incorporate wireless terminal devices and base stations (BSs) for the purpose of providing communications services, such as telephony, data, video, messaging, chat, and broadcast. Multiple wireless terminals may be connected to a serving cell that is controlled by a BS. Wireless networks may employ various access schemes, which may include frequency division multiple access (FDMA), time division multiple access (TDMA), code division multiple access (CDMA), orthogonal frequency division multiple access (OFDMA), and single-carrier frequency division multiple access (SC-FDMA). A BS may also be referred to as a NodeB in Universal Mobile Telecommunications System (UMTS), an evolved NodeB (eNB) in Long-Term Evolution (LTE) specified by the Third Generation Partnership Project (3GPP), a base transceiver system (BTS), or an access point (AP)
In general, an eNB may be a fixed hardware (e.g. not mobile), but in some cases, such as when deployed in a car, may also be mobile. A wireless terminal device may be a portable hardware and may be referred to as a user equipment (UE), a mobile station, a cellular phone, a personal digital assistant (PDA), or a wireless modem card. In wireless communication networks, uplink (UL) communication may refer to communication from a UE to an eNB, while downlink (DL) communication may refer to communication from an eNB to a UE. An eNB may comprise radio frequency (RF) transmitters and receivers used to directly communicate with UEs, which may either be in a fixed location or freely move around the eNB. Similarly, each UE may comprise RF transmitters and receivers used to communicate directly with the eNB.